10. Blowing your nose in public

In a crowded public place like a train car, emptying the contents of your nostrils into a tissue or, worse, a handkerchief is a big no-no in Japan. You’re better off doing what many others do — sniffing a lot. Every train car has its sniffers and, occasionally, some snorters too. If you must honk into your hanky, just do it as discreetly as you possibly can and try not to spend too much time gawking at the fruits of your labor once the job is done.